INTRODUCTION 1191 I. Two MODELS OF CONSTITUTIONAL PRIVACY 1197 A. Privacy Outside the Fourth Amendment 1198 B. The Myth of Fourth Amendment Neutrality 1203 II. THE FOURTH AMENDMENT'S MORALISTIC TURN 1206 A. The Moralism of "Reasonable Expectations of Privacy" 1207 B. A History of Fourth Amendment Intimacy 1212 1. Origins and Early Republic 1212 2. Early Supreme Court Precedent 1215 3. After Katz 1216 III. EXAMINING ACTUAL CONDUCT 1219 A. Aerial Surveillance of Curtilage 1220 B. Visitors in the Home 1224 C. Dog Sniffs and Drug Tests 1230 IV. AGAINST FOURTH AMENDMENT MORALISM 1236 A. Traditional Interpretive Principles 1237 1. Text 1238 2. Purpose and History 1238 3. Function 1240 B. The Value of Privacy 1244 V. BEYOND FOURTH AMENDMENT MORALISM 1250 A. Revisiting Fourth Amendment Doctrine 1251 1. Looking Past Intimacy 1252 2. Recognizing Binary Searches 1255 B. Revisiting Fourth Amendment Privacy 1258 CONCLUSION: HAS THERE BEEN A RIGHT TO PRIVACY? 1262 INTRODUCTION
In Olmstead v. United States, Justice Brandeis famously defended the "right to be let alone" as a servant of "man's spiritual nature," his "intellect," his "emotions" and "beliefs." (1) The value of privacy, by this view, was a function of a person's moral and intellectual autonomy: his right to live his own life in his own way. (2)
Since then, the Supreme Court's visions of privacy have often diverged from that liberal path. At least in its substantive privacy jurisprudence, the Court in the past five decades has struggled between two conflicting approaches--what may best be seen as diametric conceptions of the relationship between privacy and moral judgment. In one model, embodied in substantive due process and First Amendment cases like Planned Parenthood of Southeastern Pennsylvania v. Casey (3) and Stanley v. Georgia, (4) the Court has envisioned "privacy" as a shield against moral judgment: a zone where individuals may engage in activities considered devoid of value, and thereby subject to regulation in other spheres. In the other, exemplified by cases like Griswold v. Connecticut (5) and Bowers v. Hardwick, (6) it has envisioned privacy as a privilege bestowed upon certain activities precisely because they are socially valuable: a reward for doing something of established moral worth.
We do not typically think of the Fourth Amendment as part of this debate. A procedural provision curbing the state's power to watch private activities rather than to regulate them, (7) the Fourth Amendment is ostensibly blind to the legality, much less the morality, of a defendant's conduct. (8) A "critical" difference between Fourth Amendment and due process privacy, scholars have insisted, is that the Fourth Amendment "make[s] the claimant's substantive conduct irrelevant" to its analysis. (9) This is not to deny that the Fourth Amendment is, in its own way, deeply normative. As a matter of black-letter doctrine, evaluating a defendant's "reasonable" expectations of privacy entails subjective social judgments. (10) Yet this normative analysis is generally seen to address the nature of the state itself: the proper scope of the criminal justice system, or the types of police tactics we wish to sanction in a democracy. (11) In that, it might endorse certain norms of how citizens living in an orderly society interact with agents of the state. (12) But it does not parse how citizens behave by or among themselves.
This Article argues that such conventional readings miss a persistent strain in the Court's Fourth Amendment jurisprudence over the past five decades. Ever since the Court in Katz v. United States recentered the Fourth Amendment around an individual's reasonable expectations of privacy, (13) its analysis of Fourth Amendment rights has increasingly come to hang on the nature and, specifically, the social value of a defendant's conduct at the time of a search. Echoing the same moral hierarchy as in its substantive due process cases, the Court has frequently tied Fourth Amendment privacy rights to the activities implicated in a given case, privileging conventional social goods like domesticity, romantic relations, and meaningful interpersonal bonds. And in some cases--most notably those involving aerial surveillance, home visitors, and drug testing--the Court has adopted an expressly retrospective analysis, examining not just the typical uses associated with a space but the defendant's actual conduct during a police search. Granting greater protections to marital embraces than marijuana plants, to social gatherings than business visits, to sexual intimacy than drug use, the Court has measured an individual's privacy interests based on the social value of the particular acts for which privacy is claimed.
There is essentially no commentary on this trend of Fourth Amendment moralism. Scholars have noted that Fourth Amendment doctrine has sometimes privileged middle-class social and domestic arrangements, (14) yet such critiques tend to concern the distributive effects of categorical rules, drawn around broad classes of spaces rather than a defendant's actual activities there. Inversely, some scholars have observed--not without controversy--that the Court sometimes considers the information uncovered by the police in assessing the existence of a search. (15) Yet they typically characterize the Court's analysis not as a matter of moral judgment but as a shorthand for the expectations of privacy test itself: ferreting out information that is "particularly private" (16) or customarily inaccessible to the public. (17) Such scholars accept the Court's retrospective analysis as an intuitive proxy for the Katz test, ensuring greater protections for more "private" facts. (18)
This Article shows that the Court's retrospective analysis of the facts disclosed by a police search is more prevalent than commonly recognized--a trend that itself challenges conventional understandings of the Fourth Amendment as blind to a defendant's conduct. But that analysis is not based on a tautological inquiry into which facts are especially private. It reflects the Court's substantive assessments of the value of the activities disclosed, based on its views of desirable social arrangements and private pursuits. As it has played out over the past five decades, the Fourth Amendment's guarantee against unreasonable searches has not simply regulated the boundaries of the police state, or secured the individual's private life against state intervention. It has itself functioned as a form of state intervention into private life, endorsing and rewarding citizens' personal life choices.
The rise of Fourth Amendment moralism is deeply troubling, and not just because it exempts broad categories of police conduct from judicial review. The Court's moralistic appraisal of an individual's reasonable expectations of privacy squares poorly with any rigorous interpretation of the Fourth Amendment, unmoored from its text, hostile to its well-documented history, and frequently obstructive of its practical operation in regulating police tactics. Not least, the Court's moralistic approach upends prevailing understandings of privacy itself--a value extolled, by Justice Brandeis and by generations since, as a sanctuary from the scrutiny and expectations of the outside world. And it does so for often negligible practical gains, approving police tactics that could be salvaged through narrower means. Neither a natural outgrowth of the Fourth Amendment's historic emphasis on the home, nor even a symptom of Katz's more recent emphasis on privacy in search-and-seizure doctrine, the Court's frequently moralistic reasoning is an extrinsic and gratuitous restriction of Fourth Amendment rights.
Beyond simply recognizing the rise of Fourth Amendment moralism, we must thus push courts to move beyond it, restoring a richer view of the Fourth Amendment as protecting a broad realm of intellectual, expressive, and moral autonomy. Adopting a less discriminating approach is especially urgent today, as digital technologies stand poised to heighten the impact of the Court's moralistic precedent. By expanding the scope and sophistication of police searches--empowering the police to harvest only pre-identified categories of communications, for example, or to sift out only those exchanges that contain evidence of crime--digital technologies threaten to exclude vast new quantities of personal data from Fourth Amendment protection. To mitigate that risk, this Article urges two immediate amendments to the Court's reasonable expectation of privacy doctrine. First, the Court must renounce its emphasis on "intimacy" at the heart of the Fourth Amendment, extending coequal protections to more individualistic or unorthodox pursuits. Second, it must restore Fourth Amendment protection for "binary searches," which ostensibly reveal only criminal guilt but in fact touch on far broader details of private life.
More fundamentally, and speculatively, this Article joins a line of scholars who have questioned the basic adequacy of privacy as the touchstone of Fourth Amendment analysis. Particularly in light of our shifting cultural norms surrounding private data, scholars have urged the Court to abandon its privacy-based framework, proposing alternatives better suited to protecting liberal values of autonomy, self-definition, and expressive freedom in the digital age. (19) The rise of Fourth Amendment moralism provides all the more reason to revisit the doctrine, revealing the extent to which Katz's commitment to protecting individual "privacy" interests has failed on its own terms--even as that development questions the extent to which Katz's failures can be traced to the concept of privacy itself. The Court's frequently moralistic approach to Fourth Amendment privacy suggests both the importance and the profound difficulty of restoring a truly liberal Fourth Amendment.
Before proceeding, two brief clarifications are in order. First, it...